FOR FILLING: Wrap cinnamon, peppercorns and cloves in cheesecloth; secure with kitchen string. In a resealable plastic bag, combine beef, pork, wine, onion, carrot, celery, garlic, rosemary, sage and bay leaf. Press out air and seal bag; put in a bowl and marinate, refrigerated, for at least 1 hour or up to 24 hours.
Reserving marinade, strain contents of bag through a fine-mesh sieve into a large bowl. Remove and discard herbs (save spices in cheesecloth). Pat dry carrot, celery and garlic with paper towels; finely chop.
In a large heavy saucepan, heat oil, lardo and butter over medium heat until butter is melted; add chopped vegetables, reduce heat to medium-low, and cook, stirring occasionally, for 10 minutes. Add marinated meat, increase heat to high and cook for 8 minutes more, then add reserved marinade and cook until liquid is mostly evaporated, about 3 minutes. Add 2 1/4 cups water and reserved spices in cheesecloth; bring to a boil, then reduce to a very gentle simmer and cook for 1 1/2 hours.
Meanwhile, bring a medium saucepan salted water to a boil; add cabbage and cook until tender, about 5 minutes. Drain and finely chop; set aside. Make ragù.
FOR RAGU: Tie together rosemary, sage and one piece celery with kitchen string; finely chop remaining celery.
In a wide heavy pot, heat oil over medium heat. Add chopped celery, onion, herb bundle and garlic; cook, stirring occasionally, until vegetables are softened, 6 to 8 minutes. Add pork and cook, breaking up meat into bits, for 3 minutes more, then add tomato purée, tomato paste and 1 cup water; stir to combine well.
Bring sauce to a very gentle simmer and cook, uncovered, stirring occasionally, for 1½ hours. Season with salt to taste. Remove and discard celery, herbs and garlic.
FOR PASTA: In a large bowl, whisk together flour and salt. Mound flour mixture and form a well in the center. Add eggs to the well. Using a fork, gently break up yolks and slowly incorporate flour from inside rim of well. Continue until liquid is absorbed, then knead in bowl until dough forms a complete mass. Transfer to a well-floured work surface and knead for 3 to 4 minutes more. Wrap dough tightly in plastic wrap and let rest until filling is ready.
Add cabbage and sausage to filling mixture; cook for 30 minutes more, then, reserving cooking liquid, strain mixture through a fine-mesh sieve into a large bowl; discard spices in cheesecloth.
Spread solids on a large plate or baking pan and let cool to room temperature, then transfer to a bowl; add cheese, breadcrumbs, egg, salt and nutmeg, and stir to combine. Set aside filling.
Divide pasta dough into four pieces. Cover 3 pieces with plastic wrap. Flatten dough so that it will fit through the rollers of a hand-cranked pasta machine. Set rollers of pasta machine at the widest setting, then feed pasta through rollers 3 or 4 times, folding and turning pasta until it is smooth and the width of the machine. Roll pasta through machine, decreasing the setting one notch at a time (do not fold or turn pasta), until pasta sheet is about 1/16 inch thick.
Lay pasta sheet on a lightly floured work surface with the long side facing you; cut sheet, lengthwise, in half. Starting from the left end of 1 piece dough, about 2 inches from short edge, put packed 1/2 teaspoon filling onto dough. Put more dots of filling onto dough, each about 1 inch apart; top with remaining 1/2 sheet dough. Using a pasta cutter, cut pasta crosswise between dots of filling. Gently press edges to seal (if using a deckled cutter, trim for decorative look). Transfer agnolotti to a lightly floured baking sheet. Repeat with remaining dough and filling. (The agnolotti can be prepared and frozen for up to 3 months. To freeze freshly made agnolotti, freeze them first on a parchment paper-lined baking sheet. Once frozen, transfer agnolotti to well-sealed, airtight plastic freezer bags and keep frozen until ready to cook. Do not defrost before cooking.)
Bring a large wide pot of salted water to a low boil; avoid a rolling boil, which may cause the pasta to open up. Reheat ragù and cover to keep warm.
In batches of 15 to 20, cook agnolotti in water until tender, about 3 minutes (frozen pasta may take another minute or two longer). Using a slotted spoon, transfer agnolotti to a large serving bowl. Add ragù and about 1/4 cup reserved cooking liquid to moisten, or more if desired. Gently toss to combine. Serve immediately.